dowels

Dowels are cylindrical rods used to reinforce and align joints between two or more pieces. They are made from various materials, most commonly wood, metal, or plastic, and are used in a range of applications from woodworking and cabinetry to machinery and construction. Dowels can function as alignment pins, fasteners, or shear transfer elements, depending on the context and material.

Wood dowels are widely used in furniture and cabinetry. They are inserted into precisely drilled holes in adjacent pieces and secured with wood glue. Dowel joints can reinforce edge-to-face or butt joints and help maintain alignment during assembly. Common advantages include simplicity, hidden fasteners, and the ability to reproduce consistent joints with jigs and guides.

Metal dowels include dowel pins and spring or roll pins used in mechanical assemblies. They provide precise alignment and can transfer loads between components. Stainless steel and hardened steel are common choices for strength and wear resistance. Tolerances and press fits are important considerations to achieve a secure, repeatable fit.

Plastic dowels are used for lightweight or non-marking applications, such as spacers, bushings, or alignment guides in furniture and plastic assemblies. They offer low friction and corrosion resistance, often at a lower cost than metal parts.

Sizes and standards vary by material and region. Wood dowels are typically measured by diameter in millimeters or inches and matched to hole diameters. Metal dowels and pins follow engineering tolerances for fit, sometimes requiring additional methods such as clamps or presses for installation.

In construction, dowel bars or pins are used to transfer loads across joints, notably in concrete pavements and structural connections, where they help maintain alignment and distribute stresses.